These red strain relief boots are designed to work with EZ Squeeze connectors.
This boot will work with EZ-RJ45 CAT5e and CAT6 connectors. The boot is crimped at the same time as the connector. Therefore it is locked it in place giving the look of a machined Patch cord crimp.
It helps maintain the bend radius of the cable and exits the rear of the connector to easily meet Category 6 and Category 5e requirements.